Corrosion problems caused by exposure to and/or the use of chloride salt has been a longstanding problem in many applications and industries, including deicing and anti-icing for roadways and bridges (often causing rebar corrosion), oil well drilling operations, and other industrial and marine applications carried out in corrosive environments. One common industrial application of chloride salts are their use in industrial brines. A brine can be an aqueous solution of chloride salts alone, or in combination with sodium, potassium, calcium and magnesium cations.
One approach to address corrosion has been the addition of various anticorrosive agents to the chloride salts or brines in order to reduce the corrosive effect. These various additives can be expensive. To a large extent, these additives have been ineffective in controlling the corrosivity of the brines. Similarly, the use of deicing formulations, which commonly include a chloride salt, inherently have a corrosive effect upon roadways, bridges (including rebar corrosion) and the environment. Various anticorrosive additives have been used with these formulations with mixed success.
The prior art recognizes that the presence of carbohydrates such as corn syrup and molasses, often used in deicing applications, reduces or inhibits corrosion at some level. However, when corrosion is an issue that must be addressed, a separate corrosion inhibitor component is usually added to the carbohydrates. The main reason for this approach is that excessive amounts of the carbohydrate would be required in order to obtain a significant anticorrosive effect due to the relatively small amount of anticorrosive moiety contained in a given carbohydrate. In these cases, specific anticorrosive agents are selected and/or synthesized to be effective in very small concentrations (very often less than 1%) so as not to affect the essential characteristics of the carbohydrate, such as freezing point, viscosity and cost. In fact, excessive concentrations of carbohydrate to accomplish a significant reduction in corrosion could well render the carbohydrate unsuitable for its intended use (e.g., as an effective deicer).
It can be seen from above that there has been a longstanding need for a solution to these corrosion problems, including the effect on the environment.